HELP IMPORTANT TEST!! Why must animals eat food but plants do not eat food? A: Plants do not appear to eat, but they do actually eat nutrients in the soil. Animals must eat to obtain food that they can't get from the soil. B:Plants make their own food through photosynthesis. Animals must eat because they cannot make their own food. C: Plants use photosynthesis to make their own food instead of eating. Animals eat plants because they like the taste of certain fruits. B: Plants make their own food through photosynthesis, so they do not eat. Animals eat because the energy they make themselves is enough to live but not grow. By eating, they can grow big and strong.